What’s the most important aspect
of Bodybuilding? Is it Diet? Training? Rest? All three? In my opinion,
everything we do/don’t do has an effect on our hormones; therefore, it is
hormone regulation through diet, training and rest that is the most important
aspect of Bodybuilding.

We all know about the importance
of Anabolic and Catabolic hormones and the effect they have on body
composition, but there is also another set of hormones produced by your Thyroid
gland which may be having a big impact on weight gain/loss.

The Thyroid gland is one of the
largest endocrine glands and is responsible for the growth and function of many
systems in the body including the rate of metabolism (the amount of energy you
utilise on a daily basis). The Thyroid gland is located in the neck and is
controlled by the Pituitary gland which is located in the brain. The principal
hormones produced by the Thyroid gland are Thyroxine (t4) and triiodothyronine,
more commonly known as t3. It is t3
that is the biologically more active hormone out of the two and the one that
actually functions at cellular level. For this reason amongst many, t3 is
considered as being several times stronger than t4.

When your Thyroid is working
correctly, 80% of all the hormones produced by your thyroid will be t4 and 20%
will be t3. Some of this t4 is then converted into t3 in order to meet the
bodies need for energy.

How
can your Thyroid influence body composition?

Seeing as it is your Thyroid that
controls your body’s rate of metabolism, how well your thyroid is functioning
can play a huge role in your body composition.

I’m sure you’ve heard people blame
their weight gain/lack of weight loss on them having a slow metabolism. What
they are referring to is a condition called HYPOTHYROIDISM or ‘underactive
thyroid’. This is when the thyroid gland doesn’t produce enough t4 and/or t3,
or the conversion of t4 to t3 doesn’t occur at a sufficient rate. This means
fat gain is more likely because the body requires less calories on a daily
basis. Hypothyroidism is often self diagnosed and is often used as an excuse
for poor eating habits, but it can be officially diagnosed by a doctor with the
use of a blood test. As well as weight gain, sufferers may also experience
fatigue, feel the cold easily, have general muscle weakness and a slow heart
rate. All these symptoms are a result of a slowing down of the body’s functions
due to a lack of available energy. In most cases, Hypothyroidism can be
controlled by following a calorie controlled diet and correct exercise, but if
necessary Hypothyrodism can also be treated by taking Thyroxine (t4) to replace
that missing from the body. This should be prescribed by a doctor and the correct
dosage followed. Side effects are rare as the t4 is just replacing what is not
being produced naturally by the thyroid. There are many supplements available
to buy online which claim to help with thyroid function. As with all
supplements that affect your body’s hormone production, be sure to research
fully any possible negative side effects. For what it’s worth, I have an
underactive thyroid but I don’t take any medication for it; diet and training
are key and taking unnecessary hormones can cause long term damage to your
body’s own hormone production.

Ever heard someone say that they have
a fast metabolism, and that no matter how much they eat they still can’t gain
weight? This is HYPERTHYROIDISM or ‘overactive thyroid’. This is when the
thyroid produces too much t4 and t3 resulting in a high metabolic rate meaning
the body requires more energy on a daily basis. This may sound great, but
people with an overactive thyroid will not only find it hard to gain weight of
any kind, but also more specifically muscle as muscle gain requires a surplus
of calories. This can be frustrating for the individual when training and
eating hard, yet not seeing the desired results in the mirror/on the scales.
Treatment for Hyperthyroidism includes Beta blockers to decrease symptoms such
as increased heart rate, and anti-thyroid drugs to decrease the over production
of the thyroid hormones.

Just like a lot of other hormones in
your body, YOU are partly responsible for the amount you do/don’t produce. Your
diet and training can have a huge impact on the function of your thyroid gland.
If you constantly reduce calorie intake, your body will ADAPT in order to
CONSERVE energy. It does this by reducing the output from the thyroid gland of
t4 and t3, and reducing the conversion of t4 to t3 at cellular level. This will
result in a lowered metabolic rate. You can however help increase/maintain your
metabolic rate by eating and training correctly. This involves eating every 2-3
hours and exercising 4-5 times a week, with a mixture of both resistance
(weight) training and cardio.